As an alternative to the obvious addition of fenders etc, you could also consider putting out an anchor well off to the side, with just enough slack in the line to enable you to pull the craft to the dock to climb aboard, A couple of other lines to the dock would prevent it moving too far away.

Since the kayak is not very high off the water I was concerned that the bumper/fender flipped over the side like on a larger boat would just get pushed over the top of the ama and effectively do nothing. I could not really figure out a way to tie on the fender to prevent this… Maybe I could also try getting a really small fender… tie one end to the boat and weight to the other end? Or just try to bungee the fender around the ama?